Hi Gary
You are probably already aware but Generally speaking, nothing is ever 100% protected all of the time.
However, there are precautions and a layered security profile that can serve to protect your data/passwords and Master Passwords in different ways.
Precautions like "isolated Browsers", SafeZone for example, and others that protect against 'screen capture' techniques and
"Anti Keyloggers" such as KeyScrambler and Zemana Anti KeyScrambler to name just 2, that protect against any Key logging.